Here the word "mouth" represents the words that he speaks. His words are compared to a sharp sword to emphasize that they will be effective. Alternate translation: "He has made my words as effective as a sharp sword" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-simile]])
Yahweh protecting his servant and keeping his purpose secret is spoken of as if Yahweh's hand cast a shadow over him. (See: [[rc://en/ta/man/translate/figs-metaphor]])
# he has made me into a polished arrow; in his quiver he has hidden me
Yahweh's servant being able to carry out Yahweh's purposes effectively is spoken of as if the servant were a sharp, new arrow. (See: [[rc://en/ta/man/translate/figs-metaphor]])
# in his quiver he has hidden me
Yahweh protecting his servant and keeping his purpose secret is spoken of as if Yahweh kept him hidden in a quiver. (See: [[rc://en/ta/man/translate/figs-metaphor]])